How can I tell if the rear axle assembly needs replaced. This is for a 535is, 1988 model year. I had thought it was the subframe busihng but It wasn't.
Axle noise Okay what it is doing, when I back out of the drive and go down the slanted curbing it sounds like a heavy chunk of metal thunks like it is dropping a short distance. It does not do this if I back at a steep angel. If I go over a speed bumpo you can hear it also but to a leasser level. I have replaced the structs springs, and most of the bushing.
I'm not familiar with your model but the likely culprits are: Rear Shock Mount sway bar end link Which bushings have you replaced?
I'd say get your car up into the air (safely of course, on 4 jack stands, level surface (ideally good concrete), using a floor jack), and get under there and look things over. Check all bushings, the guibo, diff. mount (as mentioned), your halfshafts, tranny/engine mounts, etc. There's a lot of things that can clunk. Also check front & rear shock mounts, tie rods, steering/front suspension linkages/parts/bushings, etc.
Simple. You don't. You figure out which of the many possible causes it is and fix it. This could be as far forward as your center support bearing on the driveshaft. It could be the rubber differential mount. It could be a trailing arm bushing. It is unlikely to be any of the parts of the axle proper, because the only ones of those that can make such a noise are the CV joints and if they do, they're near death anyway. Even then, you'd probably only need one side and not the other. Do you have a Bentley E28 manual? If not, then get one (ebay, Amazon, Robert Bentley Publ., etc.). It will save you far more than the $35-45 it will cost you in aggravation and wasted effort. Then, get to work figuring out exactly what it is that sound is. If you are near any other E28ers (join up and ask at www.mye28.com), maybe we'll get together for a 'wrenchfest' for you.
Figured it out Well taking everyones input into consideration, using a very good Bently Manual and having a person with a lift get it in the air enough - It is the subframe bushings. Now I know what it is and I already have the parts - it is settign a weeknend aside to fix. Only cost me a couple cold ones after hours and lots of car chat - like that was a burden huh. Thanks all for the input.
My advice is to find someone with the tools to do the subframe bushings on the car. BMW charges 8 hours to do them! With the tool, it takes me all of an hour a side. Otherwise, you have to remove the rear subframe and press the bushings out on a press, Which is a real PITA! Your CCA chapter may have the tool.
